The clerk nods, then picks up two small tokens with loops of cord attached. She sets then in a clear spot, taps a few sigils on something behind the counter, then sets one token on a circular pad. There's a brief flash of light, and she sets that one aside, taps another couple sigils, and repeats with the second token. She gives them both to Lily.
"This one," she says, pointing at the first, "is the master key. It identifies you as the renter of the room. The other is a spare key. Spare keys can be deactivated if you present the master here at the front desk. To use it, tap either key to the metal circle above the doorknob. You'll hear the lock click open and see a small green flash."
She leans back and nods. "Welcome to the Glass Poppy. You have room 39. Enjoy your stay."